interface Person {
    firstName: string,
    lastName: string
}
function greeter(person: Person) {
    return "Hello, " + person
}

// let user = {
//     firstName:'23',
//     lastName:'34'
// }

class Student {
    fullName: string;
    constructor(public firstName,public middleInitial,public  lastName) {
        this.fullName = firstName + ' ' + middleInitial + ' ' + lastName
    }
}

let user = new Student("123","345","789");




document.body.innerHTML = greeter(user)